A telephone service provider may provide an Internet Protocol (IP) telephony service, such as Voice over IP (VoIP), for its subscribers. To receive an IP telephony call, a subscriber may have his/her E.164 telephone number registered in an ENUM database. The ENUM database and a Domain Name System (DNS) database are queried to translate the E.164 telephone number into a list of routable Uniform Resource Identifiers (URIs) associated with the subscriber. The translation may be based on a format specified by IETF RFC 3761. An incoming telephone call for the subscriber is directed to an IP end point based on a query of the ENUM/DNS databases.